Sulfate in atmosphere

Hoffer, E. M., E. L. Kothny, and B. R. Appel, Simple Method for Microgram Amounts of Sulfate in Atmospheric Particulates, Atmos. Environ., 13, 303-306 (1979). 

Aeration of ferric sulfate should be held to a minimum because of the hygroscopic nature of the material, particularly in damp atmospheres. Mixing of ferric sulfate and quicklime in conveying and dust vent systems should be avoided as caking and excessive heating can result. The presence of ferric sulfate and lime in combination has been known to destroy cloth bags in pneumatic unloading devices. Because ferric sulfate in the presence of moisture will stain, precautions similar to those discussed for ferric chloride should be observed. 

The deleterious effect of sulfur dioxide and sulfites in domestic water is increased corrosivity owing to the lowered pH. However, oxidation of sulfite to sulfate in aqueous solutions uses dissolved oxygen, and lliis may retard corrosion. While llte oxichition of sulfite and sulfiirous acid to sulfate and sulfuric acid in the atmosphere is an environmental concern, this reaction is too... 

The most important pathway of sulfur through the atmosphere involves injection as a low-oxidation-state gas and removal as oxidation-state VI sulfate in rainwater (Fig. 13-2, paths 1, 4, 5, 6, 7, 8, 9,10,12, and 13.) Since this pathway involves a change in chemical oxidation state and physical phase, the lifetime of... 

Solids containing oxidized anions (carbonates, sulfates, hydroxides, and oxides) are the dominant forms of Cu in airborne particulate matter. In the few studies that have addressed the reactions of these particles in atmospheric washout, about 50% of the copper has been found to be soluble. Since the solubility is strongly dependent on pH, acid precipitation and acidification of receiving waters may have a significant effect on the form and fate of airborne copper. 

Fig. 16-4 pH sensitivity to SO4- and NH4. Model calculations of expected pH of cloud water or rainwater for cloud liquid water content of 0.5 g/m. 100 pptv SO2, 330 ppmv CO2, and NO3. The abscissa shows the assumed input of aerosol sulfate in fig/m and the ordinate shows the calculated equilibrium pH. Each line corresponds to the indicated amoimt of total NH3 + NH4 in imits of fig/m of cloudy air. Solid lines are at 278 K, dashed ones are at 298 K. The familiar shape of titration curves is evident, with a steep drop in pH as the anion concentration increases due to increased input of H2SO4. (From Charlson, R. J., C. H. Twohy and P. K. Quinn, Physical Influences of Altitude on the Chemical Properties of Clouds and of Water Deposited from the Atmosphere." NATO Advanced Research Workshop Acid Deposition Processes at High Elevation Sites, Sept. 1986. Edinburgh, Scotland.)... 

Endosulfan is a popular pesticide with greenhouse chrysanthemum producers. Surveys of usage patterns and potential exposure were conducted in Ontario (Archibald et al. 1994b). Collection and analysis of a-and P-endosulfan and endosulfan sulfate in greenhouse air have been described (Vidal et al. 1997). Results indicate that 7.5% of the initial concentration of endosulfan remained in the greenhouse atmosphere 24 hours after application. 

The calcium sulfate in a desiccator is effective at removing water vapor only as long as some anhydrous salt remains. When all the anhydrous salt has been converted to the dihydrate, the desiccator can no longer maintain a dry atmosphere. Fortunately, the thermodynamics of this reaction makes it possible to regenerate the diying agent. At 100 °C (373 K), A S ° contributes more to A G ° than does A H ° ... 

Eatough DJ, VF White, LD Hansen, NL Eatough, JL Cheney (1986) Identification of gas-phase dimethyl sulfate and monomethyl hydrogen sulfate in the Los Angeles atmosphere. Environ Sci Technol 20 867-872. 

Forms of silver in atmospheric emissions are probably silver sulfide, silver sulfate, silver carbonate, silver halides, and metallic silver (Smith and Carson 1977). About 50% of the silver released into the atmosphere from industrial operations is transported more than 100 km and is eventually deposited in precipitation (USPHS 1990). Minute amounts of 110mAg have been detected in natural waters and are attributed to atmospheric fallout from nuclear explosions (Smith and Carson 1977). 

The method gives better yields, utilizes more readily available starting materials, and is much less laborious than the hydrolysis of N-methyl-N-alkylarenesulfonamides and -nitroso-N, N-di-alkylanilines, or the lithium aluminum hydride reduction of alkyl isocyanates. Compared to the closely related procedure of Lucier, Harris, and Korosec,12 in which the N-benzylidenealkyl-amine is treated with dialkyl sulfate at atmospheric pressure, the present procedure tends to give higher yields and purer products, but it is less convenient because of the need for a pressure vessel. 

MUler, J. M., and R. G. de Pena. The rate of sulfate ion formation in water droplets in atmospheres with different partial pressures of SO], pp. 375-378. In H. M. Englund and W. T. Beeiy, Eds. Proceedings of the Second International Clean Air Congress. Held at Washington, D.C., December 6-11, 1970. New York Academic Press. 1971. 

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